Elliptic Curve Group Law
The Group of an Elliptic Curve which has been transformed to the form
is the set of
-Rational Points, including the single Point at Infinity. The grouplaw (addition) is defined as follows: Take 2 -Rational Points 
and 
. Now `draw'a straight line through them and compute the third point of intersection 
(also a -Rational Point). Then 
gives the identity point at infinity. Now find the inverse of
, which can be done by setting 
giving 
.This remarkable result is only a special case of a more general procedure. Essentially, the reason is that this type ofElliptic Curve has a single point at infinity which is an inflection point (the line at infinity meets the curveat a single point at infinity, so it must be an intersection of multiplicity three).
- Agnesi's Witch
- Agnésienne
- Agonic Lines
- Ahlfors-Bers Theorem
- A-Integrable
- Airy Differential Equation
- Airy-Fock Functions
- Airy Functions
- Airy Projection
- Aitken Interpolation
- Aitken's Delta Squared Process
- Ajima-Malfatti Points
- Albanese Variety
- Albers Conic Projection
- Albers Equal-Area Conic Projection
- Alcuin's Sequence
- Aleksandrov-Cech Cohomology
- Aleksandrov's Uniqueness Theorem
- Aleph
- Aleph-0
- Aleph-1
- Alethic
- Alexander-Conway Polynomial
- Alexander Ideal
- Alexander Invariant